Neutrino-nucleus quasi-elastic and 2p2h interactions up to 10 GeV

TL;DR

This paper extends microscopic calculations of neutrino-nucleus interactions up to 10 GeV, analyzing 2p2h and QE processes, highlighting their significance for neutrino oscillation experiments and the impact of nuclear effects.

Contribution

It provides the first detailed analysis of 2p2h interactions up to 10 GeV, including their scaling, shape distortions, and the interplay with nuclear correlations in neutrino-nucleus reactions.

Findings

2p2h cross section is 26% of QE at 3 GeV for momentum transfer below 1.2 GeV

Long-range correlations significantly distort the four-momentum transfer shape

2p2h effects are observable and influence neutrino oscillation measurements

Abstract

We extend to 10 GeV results from a microscopic calculation of charged-current neutrino-nucleus reactions that do not produce a pion in the final state. For the class of events coming from neutrino interactions with two nucleons producing two holes (2p2h), limiting the calculation to three-momentum transfers less than 1.2 GeV produces a two dimensional distribution in momentum and energy transfer that is roughly constant as a function of energy. The cross section for 2p2h interactions scales with the number of nucleons for isoscalar nuclei, similar to the quasi-elastic (QE) cross section. When limited to momentum transfers below 1.2 GeV, the cross section is 26% of the QE cross section at 3 GeV, but 14% if we neglect a Delta1232 resonance absorption component. The same quantities are 33% and 17% for anti-neutrinos. For the quasi-elastic interactions, the full nuclear model with long range correlations produces an even larger, but approximately constant distortion of the shape of the four-momentum transfer at all energies above 2 GeV. The 2p2h enhancement and long-range correlation distortions to the cross section for these interactions is significant enough they should be observable in precision experiments to measure neutrino oscillations and neutrino interactions at these energies, but also balance out and produce less total distortion than each effect does individually.